What is USDC (USD Coin)?

USDC is a dollar-pegged stablecoin issued by Circle. Each token is meant to be redeemable for one US dollar. It is one of the most widely used dollar stablecoins, and businesses use it to hold, send and settle dollars without relying on bank hours.

How USDC works

Circle issues USDC against reserves held in cash and short-duration US Treasuries. Approved partners can mint and redeem USDC directly with Circle. Everyone else buys and sells it on exchanges and payment platforms. Redeeming back to dollars usually settles over normal banking rails.

USDC runs on many blockchains, including Ethereum, Solana, Polygon and Base. Each chain has its own fees, speed and security record, and moving between chains uses bridges. The Amboss post on accepting stablecoins without multi-chain overhead lists the costs a merchant takes on for every extra chain.

Where businesses use USDC

Paying suppliers, contractors and staff in markets where dollar access is limited.
Settling to merchants in dollars.
Holding operating cash that can move at any hour.
Collateral, lending and trading in DeFi.

Points to weigh

Centralized issuance. Circle controls minting and redemption and can freeze addresses when legally required.
Banking dependency. Reserves and redemptions rely on traditional banks.
Regulation. Stablecoin rules differ by country and are changing.
Chain risk. Each network supporting USDC has its own reliability profile.

For a comparison with the other large dollar stablecoin, see USDT (Tether).

USDC over Lightning

Taproot Assets lets a stablecoin be issued on Bitcoin and sent through Lightning channels. A payer can send bitcoin while the receiver gets a stablecoin, and the conversion happens in flight. This moves USDC-style value at Lightning speed, without a bridge or a second blockchain. See stablecoin settlement.

How Amboss handles USDC

Amboss Payments lets businesses accept and send USDC, USDT and Bitcoin over Lightning through one GraphQL API. Payments settle in seconds to the business's own wallet. Completed payments are final, with no card chargebacks. Amboss does not hold, receive or proxy the funds, and your receiving wallet determines the settlement asset. In September 2026 the median live payout settled 2.8 seconds after it was requested. See Amboss Payments for providers.

Amboss's RailsX launch post (April 2026) names USDC-L as one of two wrapped stablecoins on Taproot Assets, alongside USDT-L, that Speed Wallet built and used in production. RailsX makes them available to Lightning node operators in self-custody, with liquidity sourced through Magma. Amboss Rails lets owners deploy Bitcoin and stablecoins into Lightning liquidity and routing to earn yield, with the owner keeping custody.

Amboss publishes a USDC-L transparency page that shows USDC-L circulation next to the USDC backing.